The invention relates generally to multi-station strip metal forming presses, and more particularly to multi-station strip metal formal presses having vertically reciprocal rams and removable die sets.
Multi-station strip metal forming machines have been manufactured by The U.S. Baird Corporation, Stratford, Conn., under the trademark MULTIPLE TRANSFER.RTM., for many years. In these machines, coil strip stock is fed in widths from a fraction of an inch through up to seven inches on larger machines. Blanks are automatically cut from the strip, and vertical blank transfer mechanism positively holds and carries the blank down to the transfer level, where it is picked up by the transfer fingers of a horizontal transfer mechanism. Usually the blank is transferred through a succession of draw dies in as many as fifteen (15) individual work stations and, finally, ejected as a completed part. This type of completely automatic operation allows piercing, forming, drawing, lettering, embossing and flanging, as well as side slotting, side piercing and reverse drawing at production rates which have exceeded two hundred fifty (250) parts per minute.
In the past, The U.S. Baird Corporation has made standardized, highly precise die sets for mounting the tooling in their machine. Complete die sets can be interchanged without losing the tool adjustment thereby facilitating set up and minimizing down time. These die sets without the tooling are relatively expensive compared to conventional commercially available die sets; on the order of twenty to one.
With the advent of the concept of "just-in-time" manufacturing, parts suppliers, who are users of the MULTIPLE TRANSFER.RTM. presses, are now required to supply component parts to final assembly operations in small quantities just as the parts are ready to be assembled into the finished product. Such a system permits the final assembly organization to maintain a small or even no inventory of component parts thereby dramatically cutting its costs but increasing the burden on component manufacturers in that their production machines must be constantly producing small quantities of different components. To meet such a manufacturing strategy, the parts suppliers using MULTIPLE TRANSFER.RTM. presses must purchase several die sets which can be interchanged to minimize the down time of their machines. However, because of the high initial cost of these die sets, it becomes prohibitively expensive to have a large number of extra die sets on hand. Furthermore, the existing MULTIPLE TRANSFER.RTM.presses are not adapted to facilitate rapid and convenient changeover from one die set to the next.
The present invention is designed to overcome the above-noted limitations, and toward this end, it contemplates the provision of a novel multi-station strip forming press which is adapted to utilize commercially available, relatively inexpensive two or four-post die sets.
It is also an object to provide such a press in which the die sets can be quickly and easily interchanged to meet the needs of the "just-in-time" concept of manufacturing.
Still another object is to provide such a press which has knockout and stripper mechanisms accommodating the interchangeability of the die sets.
A further object is to provide such a press which may be readily and economically fabricated and will enjoy a long life in operation.